Step 1: Understanding the Concept:
The principle of "Non-alliance" or Non-Alignment was a cornerstone of India's foreign policy after independence, championed by Prime Minister Jawaharlal Nehru. It advocated for staying independent from the major power blocs of the Cold War. The question asks for its constitutional basis.
Step 2: Detailed Explanation:
While the term "Non-alignment" is not explicitly mentioned in the Constitution of India, its spirit is reflected in the Directive Principles of State Policy (DPSP), specifically in Article 51.
Article 51, under Part IV of the Constitution (DPSP), directs the State to:
(a) promote international peace and security;
(b) maintain just and honourable relations between nations;
(c) foster respect for international law and treaty obligations; and
(d) encourage settlement of international disputes by arbitration.
These principles form the philosophical foundation of India's policy of Non-Alignment, which seeks to promote peace, sovereignty, and cooperation without being part of military alliances. The policy is an instrument to achieve the goals laid out in Article 51.
Step 3: Final Answer:
The fundamental principle of "Non-alliance" is associated with the Directive Principles of State Policy (Article 51).